Electric annunciator



(No Model.)

H. o. THOMSON. ELECTRIC ANNUNGIATOR. No. 542,664. Patented July 16, 1895.

UNITED l STATES PATENT OFFICE.

HENRY C. THOMSON, OF BOSTON, MASSACHUSETTS, ASSIGNOR TO THE ELECTRIC GAS LIGHTING COMPANY, OF PORTLAND, MAINE.

ELECTRIC ANNUNCIATOR.-

SPECIFICATION forming part O' Letters Patent N0. 542,664, dated July 16, 1895. Application iiled Dctober 2, 1894. Serial No. 524|720 (N0 mvdeL) To @ZZ whom t may concern.`

Be it known that I, HENRY C. THOMSON, a

citizen of the United States, residing at Bos-,

' of the United States to F. NV. Ross, No.

513,956, of January 30, 1894, and No. 521,046, of Juno 5, 189i. This class of annunciators is so thoroughly described in said patents and their operation so well known in the art that it will only be necessary for me to point ont the particulars in which my invention consists in comparison with said patents. In describing my invention, I refer particularly to said Ross patent, No. 513,956, inasmuch as the changes to adapt my improvement to use in No. 521,046 will not require any detail herein.

The object of my invention is` two-fold:-

to make a saving in the expenseof operatingA the electric battery; second, to secure an improved construction of the mechanical parts of the apparatus. I can best describe ,my invention by referring to said Ross patent, No. 513,956. In said Ross invention the core of the single vertical magnet is movable within the helix of the magnet and is there retained by means of the weighted lever, which is mounted upon the opposite end of the spindle carrying the index-finger. When said magnet is energized and the movable core drawn within the same, said lever is thereby liberated and, falling, carries with it the indexlinger, which is thus made to point in any desired direction.

My invention more particularly consists in using 4a permanently-fixed core within the helix sufciently long to come down to nearly, but not quite, the end of the spool upon which the helix is Wound, then inserting in said spool asmall cylinder or section of tubing of, say, one-quarter of an inch in length, in the opposite projecting sides of which two notches are cut, and then taking a section of a core of the same size with the armature-core and ol' about, say one-eighth of an -inch in height,

and placing that within said cylinder, so that if drawn up within the cylinder it will rise higher than the said notches in the cylinder.

My i nvention will be easily understood from the accompanying drawing in section, in which Z represents the magnet; K, the cylinder within the magnet Z; C', an armature-core extending to the end ot' the spool; L, a lnovable drop or armature. The magnet is sustainedV upon the frame A. The indicatingarm G is represented by dotted lines and is upon one end. of the spindle E, which moves in the sleeve F. Upon the other end of the spindleE is carried the lever D, having the slot- 2 and theweighted end 3. The lever D is normally retained in the position shown in the drawing by the drop or armature L, but

when said armature is elevated the said leverv D will swing through the slots M M" cut in the cylinder K.

Upon any magnet Z being energized and its fixed core rendered magnetic, the drop L willr be, of course, attracted, as `would an armature by the core O of said magnet, and thus retracted above the slots MM in the cylinderpiece K. The weighted lever D will thereby be released and its edge swung through the slots M M', thus allowing its weighted end to fall and of course allowing the indexlinger to fall at the same time. Upon said .magnet being de-energized the drop L will of course return to position. The index-iinger may be restored to normal position by means of a lift, (not shown,) but which in such apparatus operatesl to elevate `the weighted end D, thereby elevating the drop L until the cam 2 repasses through the slots M M', whereupon the drop L falls into said ratchet and retains the drop in the position shown in the drawing. By means of this construction I obtain the two results which are desired, inasmuch as less electric energy will be required to lift the sma-ll drop L than Vto litt an entire core, and the mechanical construction of the apparatus is also further simplified.

Having thus described my invention, I do not claim so much asis shown in either of said patents to Ross, except so far as combined with my improvement.

What I do desire to protect by Letters Patent and to claim is- I. In an electric annunciator, in combination with an index-finger and a weighted lever, 'each mounted upon a spindle supported within a sleeve, an electro-magnet having the fixed core C', the cylinder K having the 4 notches M, M', and the drop L, substantially as described and shown.

2. In combination with an electro-magnet having a fixed core extending nearly t0 the lower end of its spool, a cylinder having opposite slots, inserted in the lower end of the spool, and a drop of abouthalf the length of the cylinder, as a trigging device in an electric annunciator, substantially as described and shown.

3. In an electric annunciator, the combination of the index-.finger G, mounted upon the spindle E, within the sleeve F, the weighted lever Dmounted also upon the end of said spindle, the magnet Z properly lixed to said face-plate, the 'fixed core C', the slotted cylinder K and the drop L, substantially as described and shown.

In Witness whereof I have hereunto subscribed my name, this 31st day of August, z5 

